(a) Field of Invention
The present invention relates to gravity-based sorting mechanisms which separate and route coins, and other disk-shaped objects, using diameter-dependent deflection.
(b) Discussion of Prior Art
Coin sorting mechanisms which operate by gravity and utilize diameter-dependent deflection are well-documented in U.S. patent literature—many descriptions date back to the late nineteenth century. Today, such gravity-based sorting mechanisms are commonly used in low-speed, cost-sensitive applications: coin validation systems represent one such application. Vending machines, and other coin-operated equipment, employ validation systems to verify the physical characteristics of deposited coins, and gravity-based sorting mechanisms generally provide the diameter-dependent separation and routing needed for this verification process.
U.S. Pat. No. 4,263,924 (R. A. Johnson, 1981) describes a gravity-based sorting mechanism designed for validation systems which separate and route multiple coin denominations. This sorting mechanism employs a hollow deflection element that pivots underneath a stationary block. The bottom portion of this stationary block contains a plurality of deflection-edges which are angled in different directions, and each deflection-edge is elevated at a different predetermined height above the floor of the hollow deflection element. Deposited coins of mixed denomination roll edgewise through the hollow deflection element, and coins of the smallest diameter roll underneath the stationary block into a particular routing channel. The deflection-edges of the stationary block selectively engage coins of each larger diameter and force the deflection element to pivot in different directions which guide these coins into their proper routing channel.
The sorting mechanism in U.S. Pat. No. 4,263,924 separates and routes a plurality of coin denominations in a very small amount of space, and this space-efficiency helps reduce the overall size of the validation system. Compact validation hardware is very important because the amount of space available inside coin-operated equipment tends to be rather limited. However, this space-efficiency is achieved through the use of a movable deflection element. Coin sorting mechanisms which utilize moving parts are expensive to manufacture and maintain; moving parts tend to wear quickly and must be cleaned and/or replaced on a regular basis to minimize the risk of mechanical failure. In these applications, such maintenance is critically important because mechanical failure can translate into lost revenue.
U.S. Pat. No. 5,988,349 (Bruner et al., 1999) describes a coin validation system which separates and routes multiple coin denominations using static deflection elements, and the elimination of moving parts reduces the manufacturing and maintenance costs of the hardware. But, each static deflection element separates and routes coins with respect to only one predetermined diameter at a time; so, multiple deflection elements must be networked together in order to process a plurality of coin denominations, and this tends to increase the overall size and complexity of the validation system.